This section provides background information related to the present disclosure which is not necessarily prior art.
Solenoid operated valves are known which provide control of a fluid such as pressurized air in operating additional equipment such as sorters, packaging machines, food processors, and the like. In order to retain the solenoid operated valve in a closed position when the solenoid is de-energized, biasing members such as springs are used. It is also known, for example in U.S. Pat. No. 4,598,736 to Chorkey, that fluid pressure can be balanced within the valve to reduce a solenoid force required to move a valve member between closed and open positions.
Known pressure balanced solenoid operated valve designs have several drawbacks however. Central passageways through the valve member are commonly provided to assist in equalizing pressure as the valve member displaces. Moisture and dirt as contaminants in the fluid, including contaminants entering at the valve discharge port, can move through the central passageway to the solenoid assembly, which can result in valve sticking, reduced valve power, or delayed operating times.